Manufacture of 1.2.5.6-dibenzophenazine and its derivatives



Patented May 16, 1933 WWI/8 ERWIN KRAMER, OF GDLOGNE-DEUTZ, BERNEAB-D BOLLWEG, 0F LEVERKUSEN, AND LUDWIG ZEH, OF \VIESDORF, GEEIMAN'Y, ASEJIGITQBS T0 GENERAL ANILINE WORKS, INC. OF NEW YORK, N. Y., A CORPORATIGN OF DELAVJ'ABIE MANUFACTURE OF l.2.5.G-DIBENZGPEENAZINE AND ITS DERIVATIVES Ne Drawing. Application filed July 10, 1930, Serial No. 467,128, and. in Germany August 3, 1929.

The present invention relates to a process of preparing azine compounds and more'particularly it relates to the manufacture of 1.2.5.6'-dibenzophenazine and its derivatives.

According to the present invention 1.2.5.6- dibenzophenazine' of the formula and its derivatives are prepared by reacting upon Q-napht-hylamme and its nuclear sub- -stitution products having a free l-position by heating to a temperature between about 100250 C. with at least the calculated quantity of a metallic oxide yielding oxygen under the conditions of the reaction, as for 7 instance copper oxide, manganese dioxide,

silver oxide, or mercuric oxide, in inert high boiling organic solvents, as "for instance trichlorobenzenes, dichlorobenzene, chloronaphthalenes until water is no longs formed in the reaction.

The new mode of Working according to the invention has the advantage oi greatv simphclty and furnishes products of great pu- W rity in a good yield.

As starting materials for the process such nuclear substitution products of 2-na hthyl amine having a free l-position come into consideration as will not be d composed or changed by the attack of the oxygen. To

I; illustrate, products such as, for instance,

parts by weight of trichlorobenzene until. no further distillation of water formed during the re ction takes place, this point being reached after approximately one hour. The trichlorobenzene is thereupon removed by means of steam distillation, the copper precipitate is dissolved by the addition of nitric acid and the 12.5.6-dibenzophenazine is filtered by suction. The crude product takes the form of slightly brownish yellow needles and has a melting point of 27 7-27 8 C. The yield amounts to over 90%. By recrystallization from trichlorobenzene pale yellow lustrous needles are obtained, which show the properties described in the literature (Beilstein IV, page 1088).

Example 2.4t0 parts by weight of B- naphthylamine are dissolved in 300 parts by weight of 1.2.4-trichlorobenzene at about 100 C. 100 parts by weight of silver oxide are added thereto; Then the tempera ture is gradually increased until the oxidation takes place very actively. In order to finish the reaction the mixture is boiled again and the 12.5.G-dibenzophenazine is isolated as mentioned in Example 1.

Example 3.-70 parts by weight of ,8- naphtl'iylamine are boiled in 400 parts by weight of 1.2.4-t ichlorobenzene with 180 parts by weight of mercuric oxide while stirring. The suspension which is at first colored red shades soon becomes black in color on the splitting of water. After boiling for about 2 hours it is cooled and the filtered ofi residue is extracted by means of hot chlorobenzene. The 1.2.5.6-dibenzophenazine sep-' arates on cooling in the form of well formed crystals and shows all the properties of the product described 111 Example 1.

Emamplc 4-445 parts by weight of B- naphthylamine mixed with 170 parts by weight of pyrolusite are boiled in 800 parts by weight of 1.2.4-trichlorobenzene for about 10 hours while stirring. The mixture is then sucked ofi" and cooled. he precipitated. 12.5.6-dibenzophenazine is cooled slightly grey shades. By rocrystallizing from trichlorobenzene or sublimation under reduced pressure it can be easily obtained in a completely pure form.

Ewaonple 5.-30 parts by weight of 6- Inethyl-2-naphthylamine and 50 parts by weight of cupric oxide are heated in trichlorobenzene as described in Example 1.

5 Bz-3-Bz3-dimethyl-1.2.5.6 dibenzophenazinc is thereby obtained. It crystallizes from nitrobenzene in yellow, lustrous necdles, which melt at 328 C. and dissolve in sulfuric acid with a brilliant blue coloration.

Ewampla 6. parts by weight of 6- brorno-Q-naphthylamine are heated with 24 parts by weight of cupric oxide in 800 parts by weight of t-richlorebenzone until the splitting oil of water has ceased. After filtering, and when cold, the trichlorobenzene is washed out, the copper precipitate isdissolved by means of dilute nitric acid and the crystalline residue is filtered by suction. The Bz -3- Bz -3- dibromo-l2.5.6-dibenzo- .phenazine crystallizes from nitrobenzene in pale yellow, strongly lustrous leaflets, which melt above 340 C. The substance dissolves in sulfuric acid with a reddish blue coloration.

Emamplc 7.70 parts by weight of 2- amino-8-naphthol-methylether are boiled with. 80 parts by weight of cupric oxide in 750 parts by weight of trichlorobenzene until the splitting oil of water is complete. The 9. further working up can follow as in Example 1 or the solution is diluted with benzene and filtered by suction. 'lhe B2;-1llz-1-dimethoxydibenzophenazine is obtained from the filtrate by distilling oil the benzene and 'subsequent steam distillation. The product crystallizes from chlorobenzene in the form of yellow needles, which melt at 222 C. From benzene large, broad, deep yellow needles are obtained, which lose their strong flustre at 100 C. and become more bright in color. In glacial acetic acid the substance dissolves with a red coloration and in sulfuric acid with a brilliant blue coloration.

Eamnple 6.59 parts by weight of 2 amino l-naphthol-inethylether are boiled with 92 parts by weight of cupric oxide in 1100 parts by weight of trichlorobenzenc until the splitting oil of water is complete. After then filtering by suction while hot and washing with hot trichlorobenzene the Ez- 2-Bz-2-dimethoxy-1.2.5.6-dibenzophenazine is obtained from the filtrate after cooling in yellow needles. It melts at 281 C. and dissolves in glacial acetic acid with a yellow coloration and in sulfuric acid with a violet coloration.

Example 9. parts by weight of 2- naphthylamino-G-sulfonic acid anilide and 48 parts by weight of cupric oxide are boiled in 600 parts by weight of trichlorobenzene until the splitting off of water is complete, then filtered by suction while hot and subse quently washed with hot trichlorobenzene. The 1.2.5.6-dibenzophenazine Bz-3-Bz-3-disulfonic acid anilide crystallizes from the liltrate in small bright greenish yellow needles. They are readily soluble in acetone and pyridine, somewhat more dilficultly soluble in nitrobenzene, rather difficulty soluble in chlorobenzene. \Vhen pure the substance melts at 326 C. The solution in sulfuric acid is violet in colour.

Example J0.32 parts by weight of monoacetyl-2:'Z-naphthylenediamine are boiled with 40 parts by weight of cupric oxide in 600 parts by weight of trichlorobenzene until the splitting oil of water is complete. Alter filtering by suction the copper precipitate is extracted with hot trichlorobenz-ene. 'lhe Bz-2-Bz-2-di (acetamino) -1.2.5.6- dibenzophenazine crystallizes from nit-robenzene in silver grey leaflets, which melt at 255 C. and dissolve in sulfuric acid with a violet coloration.

We claim:

1. Process of preparing 1.2.5.6-dibenzophena-zine compounds comprising heating a compound of the group consisting of 2- naphthylamine and its halogen-, alkyl-, alkoXy-, acylamino-, sultonamideand sulphonarylidenuclear substitution products having a free l-position at a temperature of between 100-250 C. in a high boiling inert organic solvent boiling between 100 and 50 C. in presence of a metallic oxide yielding oxygen under the conditions of reaction. 2. Process of preparing 1.2.5.6-dibenzo phenazine comprising heating 2-naphthyla-v mine at a temperature of between 100250 C. in a high boiling inert organic solvent boiling between 100 and 250 C. in presence 01" a metallic oxide yielding oxygen under the conditions of reaction.

3. Process of preparing 1.2.5.6-dibenzophenazine comprising heating 145 parts'by weight of Q-naphthylamine in 750 parts by weight of trichlorobenzene at a temperature of 180200 C. until no more water is formed in the reaction, in presence of 250 parts by weight of copper oxide.

In testimony whereof, we allix our signatures.

ERWVIN KRAMER. BERNHARD BOLIJWEG. LUDWIG ZEH. 

